Frame construction for chairs or the like



4 W. H. MURPHY FRAME CONSTRUCTION FOR CHAIRS OR THE LIKE Filed June 17, 1948 2 SHEETSISHEET 1 meo W. H. MURPHY Au 26, 1952 I FRAME CONSTRUCTION FOR CHAIRS OR 'THE LIKE Filed June 17, 1948 2 SHEETS-SHEET 2 Patented Aug. 26, 1952 UNITED FRAME CONSTRUCTION FOR CHAIRS OR THE LIKE William H. Murphy, Chicago, 111

Application June 17, 1948, Serial No. 33,623

Claims.

The present invention relates to a framework for a chair or similar article of furniture and more particularly to an improved base or ottoman construction, an improved back frame structure and improved means for distributing the load upon the base over the members forming the base.

Upholstered furniture, such as chairs, sofas and davenports, is provided with a framework which in most instances is conventionally constructed with little or no effort being made at improving the same to increase the strength, stability and durability or to reduce weight or cost of manufacture and assembly by simplifying the structure. Accordingly it is a primary object of the present invention to provide a new and improved framework for a chair or the like in which these disadvantages of conventional fram structures are obviated.

Another object of the invention is the provision of a new and improved base or ottoman construction for a chair or the like which may be constructed as a unitary subassembly.

A further object of the invention is the provision of a new and improved frame construction which is equally adaptable for use in chairs, davenports, sofas or similar articles of furniture irrespective of the size of the same.

A still further object of the invention is the provision of a framework for achair or like artide of furniture which has a new and improved joint structure of increased strength and stability for securing a back frame to the base fram so designed that the two parts may be constructed as separate subassemblies which may be secured together after they are completed to form the finished article of furniture and in which framework means are provided for distributing the load Over thebase frame members.

A more specific object of the invention is the provision of a base for a chair or the like having a new and improved joint structure for securing together the legs and side and end members of the base which is more simple and sturdy than conventional constructions used for this purpose and will sustain a greater weight than similar structures of comparable size and weight.

These and other objects, advantages and 'capabilities of the invention will becomeapparent from the following description-wherein reference is had to the accompanying drawings, in which:

Fig. 1 is a perspectiveview of the base structure for a chair with a portion of the side rails of aback frame secured to this base to show the relative position of the parts and with the springs,

2 padding, and upholstery removed from the frames more clearly to show the construction;

Fig. 2 is a vertical sectional view taken on the line 22 of Fig. 3 and showing an arm in normal position;

Fig. 3 is a horizontal sectional view taken on the line 3-3 of Fig. 2; and

Fig. 4 is an exploded view of the joint structure by means of which the rearlegs are secured to the base frame and the side rails of the back frame are secured to the base frame.

For the purpose of illustrating the principles of the invention, a base for a chair is shown in the drawings and will be described but it is to be understood that this structure with slight modification is adaptable for use in other pieces of furniture such as davenports and sofas. Referring to Fig. 1, it will beseen that this base includes a generally rectangular Wood base frame formed by opposite side rails I0, a front cross-member l2 disposed in abutting relation to theside rails, and doweled and glued thereto, and a rear crossmember l4 mortised into the side rails l0 adjacent their rear ends. A pair of wood screws may be countersunk in each side rail opposite the mortise therein so that they pass through the side rails and into the ends of the rear crossmember 14 to hold these parts in assembled relation. Additional strength. may be imparted to the union by gluing these parts together at the joints. This frame is supported by a plurality of legs including generally vertically extendin front legs l6 and rear legs l8 rearwardly inclined with respect to the front legs. I

Each of the front legs l6 includes an upper end part 20 of enlarged dimensions in a front to rear direction, and this enlarged end part is rabbeted or stepped on its front edge and its outwardly facing side to provide a lateral contact surface of considerable area and shoulders or abutments upon which th underside of the respective adjoining front cross-member l2 and the side rails l0 engage when the legs are secured in position as best seen in Figs. 2 and 3. A distinct advantage of the construction above described arises from the fact that the load on the frame is transmittedto the legs through these abutments and this manner of assembling the legs to the frame is exceedingly simple, when compared with the joint structure commonly used in securing legs to a frame. Furthermore it has greater strength than the conventional joint structures used for this purpose.

I The front legs are held in position at the inner side of the joint between the front cross-member and the side rails by means of a plurality of wood screws 22 driven through the enlarged portion 20 and into the side rails ID. The heads of these screws are preferably countersunk and the union between the legs and frame may be strengthened if desired by gluing the contiguous portions of these parts.

The rear legs l3 each include a lower end portion 24 of any desired configuration, and an upper end portion 26 formed as a continuation of this lower end portion but of enlarged dimensions in a front to rear direction as indicated in Figs. 2 and 4. An abutment or shoulder 28 extending at an inclination corresponding to the angle between the longitudinal axis of the side rails and rear legs is formed by rabbeting or stepping the laterally outwardly facing side of the upper end portion 26 at the place where it merges with the lower end portion to a depth approximating the thickness of the side rails, as shown in Fig. 4. The two rear legs are secured to the inner side of the side rails Ill forwardly of the rear cross-member 14, as shown in Fig. 2, by gluing the same thereto and by means of a plurality of wood screws 30 in a manner similar to that in which the front-legs are fixed in position. Preferably each rear leg is notched on its rearwardly facing side to provide an abutment 32 for engaging the underside of the rear cross-member (4 so that the load on the frame is transmitted to the rear legs through the abutments thereon, thus providing a sturdy but inexpensive joint structure.

Reinforcement for the frame is provided by means including a pair of triangular blocks 34, one of which is located in each of the opposite corners formed between the rear cross-member and the side rails. These blocks are glued in position and are also secured by means of a pair of wood screws indicated at 3B in Fig. 3. Additional reinforcement is provided by a pair of metal tie members 33, also best seen in Fig. 3, which extend between the front and rear crossmembers through aligned apertures therein near their lower edges. These apertures are located atapoint in the front cross member adjacent its outer ends and at a point in the rear cross member somewhat farther from its ends so that the plane .of the tie members is inclined inwardly. The tie members are operatively connected to the-cross-members bymeans of nuts 40 threaded upon the opposite ends of the tie members and engaging against the front and rear cross-members. Preferably washers 42 are interposed between the nuts and cross-members and the latter may be provided with countersunk apertures in which the nuts are disposed. The particular manner in which these tie members function to reinforce the base frame and to distribute the load thereon will be described in detail hereinafter.

l A base construction of the type abovedescribed is exceedingly simple to manufacture and assemble and, therefore, can be producedat less expense than conventional bases. Nevertheless the base is extremely sturdy and stable because of the manner in which the frame and legs are secured together. This structure, when used as the base of a chair, or when slightly modified to form the base of a sofaor davenport, may readily be provided with a back, as will appear hereinafter. In such a case the rearward inclination of the rear legs gives added stability and prevents rearward tipping of the chair or davenport.

Furthermore the manner in which the 4 rear legs are secured to the side rails tends to transmit some of the load on these legs through the side rails to the front legs, and the tie members 38 interconnect the front and rear crossmembers to increase the stability of the entire base and distribute the load thereon.

When the structure described above is to be used as a base of a chair, a back may be fixed to the rear cross-member M to become an integral part of the base in a manner which will now be described. Preferably the frame of the back includes a pair of vertically extending side rails 44 secured in spaced relation by means of upper and lower cross-members 46 and 48, respectively. The ends of these cross-members may be doweled and glued to the side rails, and the joints thus formed may be reinforced by means of triangular reinforcing blocks 50 glued and nailed along the inner sides of each of the joints. Normally a back of this type is inclined rearwardly from the vertical, as indicated inFig. 2. This inclination is secured by providing a generally vertically extending lower end 52 on the side rails, and an upper end tapering rearwardly from'ahoutthe level of the seat of the finished chair.

Although various means may be used for fixedly securing the back frame to the base, the construction which I have shown in Figs. 2 and 4 is preferred because of its inherent strength and rigidity. As indicated in Fig. 4, a vertically extending slot 54, conforming in width and length to the thickness and height of the rear crossmember [4, is cut in the lower vertical end portion 52 of each of the rails 44 in the back frame. The assembled back may be placed in position on the base by engaging these slots over the rear cross-member l4, and the back frame is fixed in centered position with respect to the rear crossmember by means of bolts 56 which extend through aligned apertures in the lower end of the side rails 44 in the back frame and the rear cross-member M in the base frame, as shown in Fig. 2.

The union between the base and back frame is reinforced by means of a pair of filler blocks .58 secured in the space between the outer sides of the back frame side rails and the rearlends of the side rails [0 in the base frama. Wood screws 60 which pass through the filler blocks and into the rear cross-member may be used to secure these blocks in position, as shown. in Fig. 3. The heads of these. screws are preferably countersunk. in the backside. of the filler blocks and theblocks may be additionally secured in position by gluing the same to the two siderails and the rear cross-member. The back sideof the filler blocks preferablyconform to the contour of the back edgeof the base and back frame side rails to facilitate upholstering of the chair.

From the above description of the improved back frame it will be apparent that it may readily be assembled as a unit and secured in position either before or after it has been upholstered. The open framework for the base and back. above described may be fitted with springs and maybe padded and upholstered in any conventional manner; but since this forms no part of the invention, a detailed description thereof is thought to be unnecessary.

While the back frameshown is narrower than the base of the chair, so that it may be provided with arms of the. type disclosed in my copending application Serial No. 759,207, filed July 5, 1947, and entitled Convertible Chair, it will be apparent that the same construction can be used in a back frame of more nearly conventional width. It is also to be understood that the base herein described could be used in constructing armless chairs and, with slight modifications, in constructing chairs havingmore or less conventional fixed arms.

As previously indicated, the chair frame above described is designed particularly for that type of chair which has hinged arms. Such arms may be constructed and secured to the back frame in the manner described in my previously mentioned application for patent and therefore will not be described in detail herein. However, as indicated in Figs. 1 and 2, each arm 62 includes a pair of side rails fi l spaced by transverse blocks 66. These arms are pivotally connected to the side rails 44 of the back frame by means of sleevelike journal members 68 fixed to the inner'si-de of the side rails 44 inthe back frame adjacent their lower ends. These sleeves rotatably receive the inner ends of hollow cylindrical shaft members l fixed to the side rails of the arms adjacent their rear ends. a

In Fig. 2 the arm '62 is shown in full lines in its lowermost position while Fig. 1 shows fragments of the arms at the limit of their raised position with their forward edges aligned with the forward edges of the back frame side rails. Cooperating means which may include a slot in the sleevelike journal members 68 and a pin or the like fixed to the hollow shafts and adapted to engage in the slots are provided for determining the limits of movement of the arms. Such means are described in detail in my copending application to which reference may be had for a full disclosure of the same.

When the arms of a chair are anchored only to the back frame in the manner above described, the forward ends have no subjacent support when the arms are in lowered position so that the strain caused, for example, by a person sitting on the arm is borne by the back frame and the rear cross member It to which it is fixed. One of the features of the present invention resides in the fact that a frame for a chair or the like constructed as described herein is sufficiently sturdy to withstand any strains which will normally be imposed upon the same even though the arms have no subjacent support.

Part of the increased strength of this frame results from the use of the tie rods 38 because these tie rods tend to transmit or distribute a part of the strain on the rear cross member l4 to the front cross member I2. This will become apparent from an inspection of Fig. 2. Assuming the weight is placed on the outer end of the arm 62, this results in a force being imposed on the back frame tending to rotate the latter in a counterclockwise direction, as seen in that figure, around its place of securement, namely, the rear cross member it. The same effect is imparted to the rear cross member along its longitudinal axis and this force is resisted on the outer ends of the same by the mortised connection between this member and the side rails. Intermediate the ends of the cross member this force is resisted by the tie rods 38 because they are fixed in the rear cross member inwardly of the place of connection between the back frame and this cross member so that these tie rods resist distortion of the rear cross member and transmit or distribute a portion of the force acting thereon to the front cross member.

It is to be understood that the invention is described as applied to a chair having two arms merely for the purpose of illustration and is not intended to be limited thereby because the same principles may be applied to the construction of chairs having one arm or no arms and to other articles of furniture which have a base'with or without a back and arms on the back.

While I have shown and described a preferre embodiment of my invention, it will be apparent that numerous variations and modifications thereof may be made without departing from the underlying principles of the invention. I therefore desire, by the following claims, to include within the scope of the invention all such variations and modifications by which substantially the results of my invention may be obtained through the use of substantially the same or equivalent means.

I claim:

1. A framework for a chair or like article of furniture comprising a base frame including front and rear cross-members and side rails joined thereto, a plurality of legs secured to said base frame for supporting the latter, a back frame including a plurality of rails fixed to the rear crossmember in said base frame adjacent the opposite ends thereof to extend substantially vertically therefrom, at least one arm supported by said back frame only and adapted to project forward;- ly therefrom so that'downward forces on the arm generate forward racking moments in said back frame, and tie members extending between said cross-members and operatively connected to said front cross-member adjacent the opposite ends thereof and to said rear cross-member inwardly of the place of attachment of the outer rails in said back frame, said tie members cooperating to distribute to said front cross-member a portion of the strain upon said rear cross-member resulting from forward racking moments in said back frame.

2. A base construction for a chair or the like comprising a frame including side and cross rails secured in abutting relation to define a seat frame of generally rectangular shape, a leg at each junction of the side and cross rails having an upper end terminating substantially at or below the upper edges of said side rails'and being enlarged in one direction, said legs being rabbeted on contiguous sides to provide shoulders for supporting the abutting side and cross rails, and means to anchor said seat frame to the upper ends of said legs'including a plurality of wood screws or the like extending into the enlarged portion of the upper end of said legs and those rails engaged against the enlarged portions of said legs.

3. A base construction for a chair or the like comprising a frame including front and rear cross members, means for securing said front and rear cross members in spaced relation including a plurality of rails joined to said front and rear cross members and extending from front to rear of said frame, front and rear legs each having an upper end of enlarged dimensions in a front to rear direction, said legs being rabbeted on two sides to provide shoulders for supporting said cross members and rails, and means to anchor said rails to the upper ends of said legs including a plurality of wood screws or the like extending through said enlarged portion of the upper ends of said legs and into said side rails, the upper ends of said rear legs terminating substantially at or below the upper edges of said side rails.

4. A framework for a chair or like article of furniture comprising a base frame including side rails and a front cross member secured in abutting relation, a rearcross member mortised in said side rails adjacent their rear ends, a plurality of legs secured to said base frame for supporting the latter, a back frame including a plurality of rails fixed to the rear cross member in said. base frame inwardly of the side rails and extending substantially vertically therefrom, at least one arm supported only by saidback frame and adapted to project forwardly therefrom so that downward forces on said arm generate forward racking moments in said back frame, and tie members operatively connected to said front cross member adjacent its lower edge and to said rear cross member adjacent its lower edge on the inner side of said back frame for distributing to said front cross member a portion of the strain upon the rear cross member resulting from forward racking moments in said back frame and thereby cooperating with the mortised connection between said side rails and cross member to resist the forces acting on the latter.

5. A base construction for a chair or the like, comprising a frame including a pair of side rails and a front cross-member, said side-rails and cross-member being adapted to be secured in abutting relation, opposite front legs having upper ends enlarged in a front to rear direction, said upper ends being stepped on at least one side and edge to provide shoulders for engaging the underside of the abutting front cross-member and side rails adjacent the joint between these parts, opposite rear legs for said frame adapted to be secured to said rails with their axes inclined rearwardly relative to said frame, said rear legs having upper ends terminating at or below the top edge of said side rails and being enlarged in a front to rear direction, said upper ends being stepped to form a shoulder inclined to the axes of the legs to adapt the same for engaging the underside of a side rail when the legs are secured to said frame, said rear legs also each having a shoulder on the rear edge thereof, means for securing said front and rear legs to said frame including wood screws or the like extending into the enlarged upper ends of said legs and the side rails, and a rear cross-member joined to said siderails rearwardly of the place of attachment of said rear legs, said rear cross-member engaging upon the shoulder in the rear edges of said rear legs.

WILLIAM H. MURPHY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 540,338 Starr June 4, 1895 602,574 Dalton Apr. 19, 1898 751,285 Herzog Feb. 2, 1904 1,519,216 Murphy Dec. 16, 1924 2,169,139 Foote Aug. 8, 1939 

